new_list = [1,2,3,4]

# 方案1
for one in new_list:
    # print(one)
    my_list = []
    for two in new_list:
        if two != one :
            my_list.append(two)
            for three in new_list:
                if three != two and three != one:
                    newstr = str(one) + str(two) + str(three)
                    print(newstr)
    # print(my_list)

